Nold buohholm



2 Sheets-Sheen.

J. A; A. BUUHHOLZ. Roller Mill forGrinding Grain, 8:0.

No 240,960. Patented May 3, I881.

1 Ill 672101 N PETERS. Phoib-Liihographcr, Washingion, D C.

Wibzasses 2 Sheets-Sheet 2. J. A.A. BUGHH-OLZ; Roller Mill for Grinding Grain, 850". I No. 240,960.

' Patente'd'May' 3, 1881.;

N. PETERS. PhotmUihogrlphar, Washington, D. C.

baa/z for UNTTED STATES PATENT Quince.

JOHN A. A. BUOHHOLZ, OF VAUXHALL, COUNTY OF SURREY, ENGLAND.

ROLLER-MILL FOR GRINDING GRAIN, 80c.

SPECIFICATION forming part of Letters Patent No. 240,960, dated May 3, 1881.

Application filed February 26, 1880. Patented in England June 3,1879, in France Novcmher17. 1879, and in Belgium January .31, 1880.

To all whom, it may concern Be it known that I, JOHN AUGUs'lE AR- NOLD BUOHHOLZ, of Vauxhall, in the county of Surrey, England, engineer, have invented an Improved Mode of and Apparatus for Beducing WVheat and other Grain to Flour, of which the following is a specification.

The object of this invention is to reduce corn to flour and to disengage the floury particles from the bran by a more simple arrangement of mechanism than has hitherto been employed for that purpose.

According to this invention I submit wheat or other grain to'the action of two pairs of crushing or grinding surfaces acting in suc cession, the one pair acting on the grain as it enters the machine, and the other pair on the residue of the crushed grain after the flour produced by the first crushing action has been removed therefrom.

In the accompanying drawings I have shown a novel arrangement of roller-mill in which three crushing orgrinding rollers are used, in combination with a sifting apparatus that serves to transmit the meal from one pair of crushing-surfaces to the other. The first and second of these rollers operate on the grain as it is fed to the machine, and the second and third rollers operate on the meal produced by the first crushing operation, such meal, in its progress to the bite of the second and third rollers, being deprived of the flour which it contains by the action of the sifting apparatus. The crushing-rollers I prefer to make of chilled cast-iron, the first and second rollers being grooved, and the third smooth or fluted more finely than the others. I have obtained a good result by the use of rollers the first of which has twelve grooves to the inch and the second twenty grooves to the inch, the third being a plain roller. A satisfactory result has also been obtained by grooving the first roller ten to the inch, the'second roller fif teen to theinch, and the third roller thirty to the inch.

Figure l is a side elevation, Fig. 2 a front elevation, and Fig. 3 a cross-section, of myimproved flour-mill; and Fig. 4 is a plan of the same, showing the frame in section on a level with the middle roller.

I may here observe that I prefer to use for fixed in the standards A, which are bolted to the bed-plate and are braced together at top by a stay-bolt. The axles of the top and bottom rollers, O and E, rotate in bearings set a little out of line with the axes of the middle roller, and forming the extremities of pairs of rocking arms 0 E, which are strung on transverse rods 0 E, that have a horizontal adjustnient in the standards. The object of thus mounting these rollers is to allow of their being swung away from the middle roller and of being readily brought into contact therewith. The rods E are adjusted by means of screws turning in bearings on the framing and tapped into the ends of the rods, as shown at Fig. 3, for the purpose of insuring the parallelism of the rollers O and E with the roller D.

The middle roller-axle carries the drivingpulley G, and also a spur-wheel, H, which gears into spur-pinions I and K on the axles of the rollers O and E. The spur-wheel H has, by preference, three times the number of teeth of the pinions l and K, and makes, say, two hundred revolutions per minute. The rollers I prefer to make of about eight and a half inches in diameter. The axles of the rollers G and E are furnished outside the standards with frietion-wheels, over which a ring, L, is sprung for transmitting direct to the rollers the pressure required for reducing the grain, the pressure being adjusted by tension-wheels projecting from carriers M, which slide in dovetailed grooves on the standards A. For keeping 5 N is the feed-hopper, fitted with a feed-roller in the usual manner.

Attached to this machine is an arrangement of sifting apparatus for receiving themeal or crushed corn from between the rollers O and D, sifting out the flour from the same, and then delivering the tailings of the meal to the action of the rollers D and F. This apparatus is best shown in the vertical section, Fig. 3, where O and l are two rectangular sieves mounted in pairs of cast-iron cheeks O P, having lugs to receive transverse supportingrods, which are carried by two pairs of cranked rock-levers, Q, These rock-levers are pivoted to stay-rods R R, which are made fastto the bracket-arms A. Below the sieves O and l? the checks are fitted with trays or bottom plates for receiving the flour as it is sifted out from the meal. These trays are so arranged with respect to each other that the upper tray, will discharge its flour from the rear onto the tray P below, which tray will, in turn, discharge its contents from its front edge into a receiver, S.

A reciprocating motion is imparted to the sieves, by means of an eccentric motion, in the following manner: Fitted to the axle of the roller 0 is a pair of eccentrics, c, which, through eccentric-rods 0, connected with the upper ends of the cranked levers Q, impart a reciprocating motion to the sieves. The result of this action is to cause the meal received onto the upper sieve, O, to travel toward its rear and to fall overonto the sieve P below, to which itis guided by means of a spout, U, inclining slightly inward and contracting laterally toward the lower sieve, in order to provide a space on either side thereof for passages V, which serve to conduct the flour from the upper to the lower tray.

The sieve 0, it will be seen, is inclined upward toward the rear, and the sieveP is inclined upward toward the bite of the rollers D and E. This inclination upward in the direction the meal has to traverse serves to intensify the action of the sieves, and thereby to economize sifting-surface.

The action of the machine is as follows: The grain, as it leaves the hopper N, is guided by inclined boards into the bite of the first pair of crushing-surfaces, in passing through which it is reduced to meal which contains a large proportion of fine flour. The meal thus formed falls onto the upper sieve, 0, where, by reason of the fineness of the gage of the woven-wire cloth, most of the flour is sifted out into the tray below, (such product being a mixture of mar ketable flour, known usually as middlings,) when ee it is discharged onto the tray below the sieve P. The coarser particles, meanwhile, (mostly in the form of rough bran,) are jogged upward, and, dropping over the upper edges of this sieve, fall down the spout U onto the lower sieve,l?, which sifts out the fine flour-particles that have escaped the action of the upper sieve, O. The total amount of flour thus sifted out will be found to equal, say, from fifty to sixty per cent., by weight, of the wheat, according to its degree of hardness or mellowness, of which about two-thirds will be tine flour and the remainder middlings. The removal of the flour at this stage will greatly facilitate the treatment of the tailings. The residue of the meal (chiefly coarse bran) is led between the rollers D E, by which it is finally crushed, and thus cleared of flour-particles.

The tinting of the rollers most suitable for the above purpose will depend on the nature of the grain to be operated upon but the examples given above sutficiently illustrate the variations of the gage which I have found it desirable to make in thecrushing-rollers. The result is not, however, essentially modified, whether the tluting be made a little coarser or alittle finer. .In cross-section the flutingshould not form sharp edges, and I use, by preference, fiuting such as that shown in the diagram, Fig. 1"; or ratchet-tooth-sha ed tinting may be used when worked back to back, as shown in the diagram, Fig. l The lengths of the arrows indicate the ditterence of speeds.

Having now explained the nature of my invention, I wish it to be understood that I claim- In combination with a mill having three rollers arranged horizontally one above another, the sifting and transferring apparatus, comprising the upper sieve, O, inclined upward and outward from the rollers, the lower sieve, P,-inclined upward and inward toward the rollers, the trays O 1? below said sieves, and the spouts for delivering coarser material from the upper sieve to the lower sieve and for delivering finer material from the upper tray to the lower tray, and mechanism for shaking said sieves and trays, substantially as herein described.

Dated the 6th day of January, 1880.

J. A. A. BUOHHOLZ.

Witnesses:

(J. BARLOW, Josnrrr STANLEY. 

